Optical fiber connector for multi-fiber cable

ABSTRACT

Optical connector arrangements terminate at least seventy-two optical fibers. The optical connector arrangements include multiple optical ferrules that each terminates multiple optical fibers. Some example optical connectors can terminate about 144 optical fibers. Each optical connector includes a fiber take-up arrangement and a flange extending outwardly from a connector housing arrangement. The fiber take-up arrangement manages excess length of the optical fibers. A threadable coupling nut can be disposed on the connector housing arrangement to engage the outwardly extending flange. Certain types of optical connector arrangements include furcation cables spacing the connector housing arrangement form the fiber take-up arrangement.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/208,829, filed Jul. 3, 2014; U.S. Provisional Application No.62/085,884, filed Dec. 1, 2014; and U.S. Provisional Application No.62/150,575, filed Apr. 21, 2015, the disclosures of which are herebyincorporated herein by reference.

BACKGROUND

Optical networks are becoming prevalent in part because serviceproviders want to deliver high bandwidth communication capabilities tocustomers. Such networks employ optical fiber cables that carry multipleoptical fibers. The optical fibers can be transitioned out of the cablesat various network nodes and routed to various communicationscomponents.

In general, optical fibers are connected to other optical fibers bysplicing or by aligning optical connectors that terminate the ends ofthe optical fibers. Some optical connectors terminate only a singleoptical fiber each. Other optical connectors (e.g., an MPO connector)can terminate up to about twenty-four optical fibers.

Improvements are desired.

SUMMARY

In accordance with some aspects of the disclosure, a multi-fiber cableassembly includes a multi-fiber cable including a plurality of opticalfibers, a strength member, and an outer jacket; a plurality ofmulti-fiber optical ferrules that each receive optical signals carriedby some of the plurality of optical fibers; a fiber take-up arrangementat which excess length of the optical fibers is stored; an anchorsection configured to secure the strength member of the multi-fibercable; a connector housing arrangement including an outwardly extendingflange; and a twist-to-lock fastener that mounts around the connectorhousing arrangement. The anchor section also defines a fiber passagethrough which the optical fibers extend towards the optical ferrules.The fiber take-up arrangement is structured to enable the optical fibersto be wrapped around the fiber take-up arrangement to manage excesslength of the optical fibers. The twist-to-lock fastener has engagementstructure that enables the twist-to-lock fastener to couple to acomponent. The twist-to-lock fastener also has an interior abutmentsurface that aligns with the outwardly extending flange of the connectorhousing to secure the connector housing to the component.

In certain implementations, the fiber take-up arrangement is disposed atthe connector housing arrangement.

In certain implementations, the anchor section is disposed at theconnector housing arrangement.

In certain implementations, a furcation cable extends between the fibertake-up arrangement and the connector housing arrangement. The furcationcable is more flexible than the multi-fiber cable.

In certain examples, the fiber take-up arrangement includes the anchorsection. In examples, the anchor section includes a cavity at which ananchor boot attached to the strength member of the multi-fiber cable isinserted. In examples, the anchor section is a first anchor section. Thefiber take-up arrangement also includes a second anchor sectionconfigured to receive a strength member of the furcation cable. In anexample, the connector housing arrangement includes a third anchorsection configured to receive the strength member of the furcationcable.

In certain examples, the fiber take-up arrangement includes a mandrelarrangement configured to hold the excess length of the optical fibersand a sealing arrangement providing an environmentally seal between themulti-fiber cable and the furcation cable. In examples, the mandrelarrangement includes a first anchor body separated from a second anchorbody by a drum. The anchor bodies define cavities to receive strengthmembers of the multi-fiber cable and the furcation cable. In examples,the sealing arrangement includes a closure member configured to surroundthe mandrel arrangement, first and second end members that attach toopposite ends of the closure member, and heat recoverable sleeves thatattach to the first and second end members.

In certain examples, the connector housing arrangement holds themulti-fiber optical ferrules. In examples, the connector housingarrangement includes a front housing and a coupling sleeve. The fronthousing defines a connection end face at which the multi-fiber opticalferrules are accessible. The coupling sleeve is configured to extendaround the front housing over a majority of the length of the fronthousing.

In examples, the front housing defines an anchor end at which a strengthmember of the furcation cable can be retained. In an example, the fronthousing includes a transition region disposed between the connection endface and the anchor end.

In examples, the front housing includes a first housing section and asecond housing section that cooperate to hold the multi-fiber opticalferrules therebetween. The coupling sleeve retains the first and secondhousing sections together.

In examples, the coupling sleeve defines the outwardly extending flange.In an example, the coupling sleeve carries an external gasket.

In certain examples, the front housing includes a first housing section,a second housing section, and a third housing section. The connectionend face is defined by the first housing section.

In examples, the first housing section defines a retention arrangementthat temporarily holds the optical ferrules at the first housing sectionuntil the second and third housing sections are coupled to the firsthousing section.

In certain implementations, flanges extend forwardly of the multi-fiberoptical ferrules to form an interrupted wall.

In certain implementations, an optical adapter connected to theconnector housing arrangement. In certain examples, the optical adaptercarries a plurality of second multi-fiber ferrules terminating secondoptical fibers. The second multi-fiber ferrules carried by the opticaladapter align with the plurality of multi-fiber optical ferrules so thatthe optical fibers of the multi-fiber cable are optically coupled to thesecond optical fibers. In examples, the optical adapter includes a firsthousing and a second housing that sandwich a ferrule plug arrangementtherebetween.

A variety of additional inventive aspects will be set forth in thedescription that follows. The inventive aspects can relate to individualfeatures and to combinations of features. It is to be understood thatboth the forgoing general description and the following detaileddescription are exemplary and explanatory only and are not restrictiveof the broad inventive concepts upon which the embodiments disclosedherein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the description, illustrate several aspects of the presentdisclosure. A brief description of the drawings is as follows:

FIG. 1 is a front perspective view of an example multi-fiber cableterminated by an optical connector configured in accordance with theprinciples of the present disclosure;

FIG. 2 is a front perspective view of the cable and components of theoptical connector of FIG. 1 axially exploded from each other;

FIG. 3 in an enlarged view of a portion of FIG. 2;

FIG. 4 is a bottom perspective view of a portion of FIG. 2;

FIG. 5 is an axial cross-sectional view of the cable and opticalconnector of FIG. 1 taken along the 5-5 line of FIG. 1;

FIG. 6 is an axial cross-sectional view of the cable and opticalconnector of FIG. 1 taken along the 6-6 line of FIG. 1;

FIG. 7 is a front perspective view of another example multi-fiber cableterminated by an optical connector configured in accordance with theprinciples of the present disclosure;

FIG. 8 a front perspective view of the cable and components of theoptical connector of FIG. 7 axially exploded from each other;

FIG. 9 a rear perspective view of FIG. 8;

FIG. 10 is an axial cross-sectional view of the cable and opticalconnector of FIG. 7 taken along the 10-10 line of FIG. 7;

FIG. 11 is an axial cross-sectional view of the cable and opticalconnector of FIG. 7 taken along the 11-11 line of FIG. 7;

FIG. 12 is a front perspective view of another example multi-fiber cableterminated by an optical connector configured in accordance with theprinciples of the present disclosure;

FIG. 13 is a rear perspective view of the cable and optical connector ofFIG. 12 with a twist-to-lock fastener retracted from an adapterarrangement to reveal a coupling sleeve;

FIG. 14 shows the cable and optical connector of FIG. 13 with thecoupling sleeve removed;

FIG. 15 is a front perspective view of an axial cross-section of thecable and optical connector of FIG. 13; and

FIG. 16 is a rear perspective view of the axial cross-section of thecable and optical connector of FIG. 13;

FIG. 17 is a front perspective view of another example multi-fiber cableterminated by an optical connector configured in accordance with theprinciples of the present disclosure;

FIG. 18 is a front perspective view of the cable and components of theoptical connector of FIG. 17 axially exploded from each other;

FIG. 18A is a rear perspective view of an alternative cable andcorresponding components suitable for use with the optical connector ofFIG. 17;

FIGS. 19 and 20 are perspective view of some of the components of theoptical connector of FIG. 17 exploded from other components;

FIG. 21 is a plan view of a longitudinal cross-section of the assembledoptical connector of FIG. 17;

FIG. 22 is a side elevational view of another longitudinal cross-sectionof the assembled optical connector of FIG. 17;

FIG. 23 is a perspective view of the optical connector of FIG. 17aligned with an example connector dust cap;

FIG. 24 is a perspective view of the connector dust cap of FIG. 23;

FIG. 25 is a perspective view of the optical connector of FIG. 17aligned with an example adapter;

FIG. 26 is a top plan view of a longitudinal cross-section of theadapter of FIG. 25;

FIG. 27 is a rear perspective view of the adapter of FIG. 25 with aferrule plug and ferrule arrangement exploded rearwardly from aremainder of the adapter;

FIG. 28 is a transverse cross-sectional view of the adapter of FIG. 25where connection end faces of the ferrule arrangement are visible;

FIG. 29 is a perspective view of the ferrule plug of FIG. 27;

FIG. 20 is a side elevational view of a longitudinal cross-section ofthe optical connector and adapter of FIG. 25 assembled together;

FIG. 31 is a perspective view of the adapter of FIG. 25 aligned with anadapter dust plug;

FIG. 32 is an exploded view of the adapter dust plug;

FIG. 33 is a front perspective view of another example multi-fiber cableterminated by an optical connector arrangement configured in accordancewith the principles of the present disclosure, the optical connectorarrangement including a connector housing arrangement and a fibertake-up arrangement;

FIG. 34 is an exploded view of the fiber take-up arrangement of FIG. 33;

FIG. 35 is a perspective view of a mandrel arrangement of the fibertake-up arrangement of FIG. 34;

FIG. 36 is an axial cross-sectional view of the fiber take-uparrangement of FIG. 33;

FIG. 37 is an axial cross-sectional view of the fiber take-uparrangement of FIG. 33 that is rotated 90° from the cross-sectional viewof FIG. 36;

FIG. 38 is a perspective view of the connector housing arrangement ofFIG. 33;

FIG. 39 is an exploded view of the connector housing arrangement of FIG.38;

FIGS. 40 and 41 are perspective views of first and second housingsections, respectively, of the connector housing arrangement of FIG. 39;

FIG. 42 is an axial cross-sectional view of the connector housingarrangement of FIG. 36;

FIG. 43 is an axial cross-sectional view of the connector housingarrangement of FIG. 36 that is rotated 90° from the cross-sectional viewof FIG. 42;

FIG. 44 is a front perspective view of the optical connector arrangementof FIG. 33 received at a port of an adapter configured in accordancewith the principles of the present disclosure;

FIG. 45 is an exploded view of the adapter shown in FIG. 44;

FIG. 46 is an axial cross-sectional view of the adapter of FIG. 45;

FIG. 47 is an axial cross-sectional view of the adapter of FIG. 45 thatis rotated 90° from the cross-sectional view of FIG. 46;

FIG. 48 is an axial cross-sectional view of the optical connectorarrangement and adapter of FIG. 44;

FIG. 49 is an axial cross-sectional view of the optical connectorarrangement and adapter of FIG. 44 that is rotated 90° from thecross-sectional view of FIG. 48;

FIG. 50 is a front perspective view of another example connector housingarrangement suitable for use with the fiber take-up arrangement of FIGS.33-37;

FIG. 51 is an exploded view of the connector housing arrangement of FIG.50;

FIG. 52 is an exploded, front perspective view of a front housing andcoupling sleeve of the connector housing arrangement of FIG. 50;

FIG. 53 is an exploded, rear perspective view of a front housing andcoupling sleeve of the connector housing arrangement of FIG. 50;

FIG. 54 is a perspective view of an example optical adapter suitable foruse with the connector housing arrangement of FIG. 50;

FIG. 55 is an exploded, front perspective view of the optical adapter ofFIG. 54;

FIG. 56 is an exploded, rear perspective view of the optical adapter ofFIG. 54; and

FIG. 57 is a perspective view of the connector housing arrangement ofFIG. 50 received at a port of the optical adapter of FIG. 54.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects of the presentdisclosure that are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

Referring to the figures in general, the present disclosure relatesgenerally to an optical fiber connector arrangement 100, 200, 300, 400,600 for a multi-fiber cable 105, 205, 305, 405, 605. The optical fiberconnector arrangement 100, 200, 300, 400, 600 includes a connectorhousing arrangement 110, 210, 310, 410, 610, 810 defining an anchorsection 112, 212, 312, 412, 612, 812 for the multi-fiber cable;multi-fiber optical ferrules 125, 425, 625, 825 that each terminatemultiple optical fibers of the multi-fiber cable; and a fiber take-uparrangement 160, 260, 360, 460, 660. In some implementations, the fibertake-up arrangement 160, 260, 360, 460 is disposed at the connectorhousing arrangement 110, 210, 310, 410 (see FIGS. 2, 8, 15, and 18). Inother implementations, the fiber take-up arrangement 660 is spaced alongthe cable 605 from the connector housing arrangement 610, 810 (see FIG.33).

In some implementations, the optical fiber connector arrangement 100,400, 600 includes bare optical ferrules 125, 425, 625, 825 (e.g., seeFIGS. 1, 19, 39, and 52). In other implementations, the optical fiberconnectors 200, 300 include multi-fiber connectors 120 (e.g., MPOconnectors) or portions thereof. For example, an MPO connector 120includes a multi-fiber ferrule 125, a connector housing 121 that carriesthe ferrule 125, and a grip sleeve 127 that aids in disengaging the MPOconnector 120 from a receptacle (e.g., an optical adapter port). Sometypes of connector housings 121 can hold springs to bias the ferrules125. Some types of connector housings 121 help with ferrule alignmentand/or protection. Some of the optical fiber connectors 300 disclosedherein include MPO connectors 120 (see FIG. 13). Others of the opticalfiber connectors 200 disclosed herein include the connector housing 121(see FIG. 8).

Each ferrule 125, 425, 625, 825 is configured to receive one or moreoptical fibers 106, 206, 306, 406, 606. In certain examples, eachferrule 125, 425, 625, 825 is configured to receive multiple opticalfibers 106, 206, 306, 406, 606. In various examples, the ferrules 125,425, 625, 825 can be configured to receive two fibers, four fibers, sixfibers, twelve fibers, twenty-four fibers, thirty-six fibers,forty-eight fibers, seventy-four fibers, ninety-six fibers, one hundredforty-four fibers, or any other desired number of fibers.

The connector housing arrangement 110, 210, 310, 410, 610, 810 has aconnection end 111, 211, 311, 411, 611, 811 at which the opticalferrules 125, 425, 625, 825 are accessible (see FIGS. 1, 7, 12, 17, 33,and 50). For example, each optical ferrule 125, 425, 625, 825 can bedisposed in one of multiple openings defined at connection end 111, 211,311, 411, 611, 811. In certain examples, the ferrules 125, 425, 625, 825are biased out of the openings with springs (e.g., coil springs, leafsprings, etc.). In some implementations, the ferrules 125, 425, 625, 825can be individually spring-biased. In other implementations, one springcan bias two or more ferrules 125, 425, 625, 825. In an example, all ofthe ferrules 125, 425, 625, 825 can be biased by a single spring. Instill other examples, the ferrules 125, 425, 625, 825 can be axiallyfixed at the connection end 111, 211, 311, 411, 611, 811.

In some implementations, the optical ferrules 125, 425, 625, 825 extendforwardly of the respective connection end 111, 211, 411, 611, 811 (seeFIGS. 1, 7, 17, 33, and 50). In other implementations, the opticalferrules 125, 425, 625, 825 are recessed within the openings (see FIG.12). For example, the optical ferrules 125, 425, 625, 825 can bedisposed within ports of an adapter mounted to the connection end of theoptical fiber connector 300 as will be described in more detail herein.

The connector housing arrangement 110, 210, 310, 410, 610, 810 has ananchor section 112, 212, 312, 412, 612, 812 at which the multi-fibercable 105, 205, 305, 405 or a furcation cable 695 coupled to themulti-fiber cable 605 is received (see FIGS. 5, 6, 10, 11, 15, 20, 36,and 52). In certain implementations, one or more strength members 107,207, 407, 697 of the multi-fiber cable 105, 205, 305, 405 or furcationcable 695 are secured (e.g., crimped, glued, hooked, wrapped around,etc.) at the anchor section 112, 212, 312, 412, 612, 812. Optical fibers106, 206, 306, 406, 606 of the multi-fiber cable 105, 205, 305, 405, 605extend through the anchor end 112, 412, 612, 812, through the connectorhousing arrangement 110, 210, 310, 410, 610, 810, and to the opticalferrules 125, 425, 625, 825 at the connection end 111, 211, 311, 411,611, 811.

In some implementations, a flat drop cable 105, 205, 305, 405 or flatfurcation cable 695 includes two strength members 107, 207, 307, 407,697 (e.g., fiber reinforced epoxy rods) that anchor to the connectorhousing arrangement 110, 210, 310, 410, 610, 810. For example, the twostrength members 107, 207, 307, 407, 697 can be inserted into cavitiesdefined at the anchor section 112, 212, 312, 412, 612, 812 (e.g., seeFIGS. 21, 42, and 52). In other implementations, other types of cables(e.g., round cables) and/or cables having other types of strengthmembers (e.g., aramid yarn, fiberglass strands, etc.) can be anchored tothe connector housing arrangement 110, 210, 310, 410, 610, 810 (e.g., byadhesive, crimping, etc.).

The fiber take-up arrangement 160, 260, 360, 460, 660 is configured tomanage excess length of the optical fibers before the optical fibersreach the connection end 11, 211, 311, 411, 611, 811 of the connectorhousing arrangement 110, 210, 310, 410, 610, 810. In someimplementations, the fiber take-up arrangement 160, 260, 360, 460 isdisposed at the connector housing arrangement 110, 210, 310, 410, 610,810. In other implementations, the fiber take-up arrangement 660 isspaced from the connector housing arrangement 610, 810. In suchimplementations, the fiber take-up arrangement 660 anchors themulti-fiber cable 605 and receives the optical fibers 606 thereof. Theoptical fibers 606 extend from the fiber take-up arrangement 660 alongthe furcation cable 695 to the connector housing arrangement 610, 810.

In some implementations, the optical cable 105, 205, 305, 405, 605 issealed to the optical fiber connector arrangement 100, 200, 300, 400,600. Sealing between the cable 105, 205, 305, 405, 605 and the connectorarrangement 100, 200, 300, 400, 600 can be accomplished using radialseals, axial seals, and heat recoverable sleeves 455, 655, 678, 878. Insome implementations, the optical cable 105, 205, 305, 405 is sealed tothe connector housing arrangement 110, 210, 310, 410. In otherimplementations, the optical cable 605 is sealed to the fiber take-upsection 660 of the connector arrangement 600 and the furcation cable 695is sealed to the fiber take-up section 660 and the connector housingarrangement 610, 810.

In some implementations, the optical fiber connector arrangement 100,200, 300, 400, 600 provides environmental protection when the connectorarrangement 100, 200, 300, 400, 600 is received at a component (e.g., anoptical adapter 500, 700). For example, in some implementations, theoptical fiber connector arrangement 100, 200, 300, 400, 600 can includea gasket or other sealing member that provides a seal between theoptical fiber connector arrangement 100, 200, 300, 400, 600 and thecomponent. Sealing between the component and the connector arrangement100, 200, 300, 400, 600 can be accomplished using radial seals and/oraxial seals. In an example, an O-ring 135, 235, 435, 635, 835 can beprovided on the connector housing arrangement 110, 210, 310, 410, 610,810. In another example, the gasket 135, 235, 435, 635, 835 can beprovided on another portion of the connector arrangement 100, 200, 300,400, 600. In other implementations, the optical fiber connectorarrangement 100, 200, 300, 400, 600 can be configured to press against agasket or sealing member disposed at the component (e.g., within areceptacle defined by the component).

In some implementations, the environmental seal between the opticalfiber connector arrangement 100, 200, 300, 400, 600 and the component isactivated by a twist-to-lock fastener 140, 240, 340, 440, 640, 840. Atwist-to-lock fastener connects a first object to a second object bytwisting (e.g., rotating) the fastener to connect the fastener to thesecond object while the fastener is engaged with the first object.Non-limiting examples of twist-to-lock connections include threadedconnections and bayonet connections. In an example, the twist-to-lockfastener 140, 240, 340, 440, 640, 840 includes an external threadedsurface to engage an internal threaded surface of the component. Inanother example, the twist-to-lock fastener 140, 240, 340, 440, 640, 840includes an internal threaded surface to engage an external threadedsurface of the component. In an example, the twist-to-lock fastener 140,240, 340, 440, 640, 840 includes part of a bayonet connection to matewith a corresponding part of the bayonet connection on the component.

In certain implementations, the twist-to-lock fastener 140, 240, 340,440, 640, 840 can be disposed over the connector housing arrangement110, 210, 310, 410, 610, 810, which includes an outwardly extendingflange 134, 234, 334, 434, 634. To connect the optical connectorarrangement 100, 200, 300, 400, 600 to the component, the twist-to-lockfastener 140, 240, 340, 440, 640 is moved relative to the connectorhousing arrangement 110, 210, 310, 410, 610 to abut the outwardlyextending flange 134, 234, 334, 434, 634, 834. The twist-to-lockfastener 140, 240, 340, 440, 640, 840 is twisted to engage the component(e.g., to engage a threaded surface, to engage a bayonet surface, etc.)to trap the outwardly extending flange 134, 234, 334, 434, 634, 834between the component and the twist-to-lock fastener 140, 240, 340, 440,640, 840. In an example, the gasket or seal 135, 235, 435, 635, 835 canbe provided on or in the twist-to-lock fastener 140, 240, 340, 440, 640,840.

Five example optical connector arrangements 100, 200, 300, 400, 600suitable for use in termination a multi-fiber cable 105, 205, 305, 405,605 are described in more detail herein. Each of these optical connectorarrangements 100, 200, 300, 400, 600 is configured to terminate at least72 optical fibers. In certain examples, each of these optical connectorarrangements 100, 200, 300, 400, 600 is configured to terminate at least96 optical fibers. In certain examples, each of these optical connectorarrangements 100, 200, 300, 400, 600 is configured to terminate at leastone 108 optical fibers. In certain examples, each of these opticalconnector arrangements 100, 200, 300, 400, 600 is configured toterminate at least one 144 optical fibers.

FIGS. 1-6 illustrate one example optical fiber connector 100 including aconnector housing arrangement 110, optical ferrules 125 carried by theconnector housing arrangement 110, and a fiber take-up arrangement 160disposed within the connector housing arrangement 110. The connectorhousing arrangement 110 defines a transition region 113. Optical fibers106 of the multi-fiber cable 105 enter the connector housing arrangement110 at the anchor end 112 and are routed through the transition region113 of the connector housing arrangement 110 to the optical ferrules125.

In some implementations, the connector housing arrangement 110 includesa front housing 117 and a coupling sleeve 130. The front housing 117defines the connection end face 111, the anchor end 112, and the take-uparrangement 160. In some implementations, the front housing 117 includesan integral housing. In other implementations, however, the fronthousing 117 includes a first housing section 119 a and a second housingsection 119 b. In certain examples, the first and second housing parts119 a, 119 b cooperate to retain the ferrules 125. In an example, thefirst and second housing parts 119 a, 119 b are identical.

In some implementations, the connection end face 111 of the fronthousing 117 defines one or more openings 114 at which the opticalferrules 125 are accessible. For example, each housing part 119 a, 119 bmay define open-ended slots or notches that align to form the openings114. In the example shown, each ferrule 125 mounts in a respective oneof the openings 114. For example, each ferrule 125 may include ashoulder 126 that abuts a retention surface at the opening 114. Eachferrule 125 may be individually spring-biased within the respectiveopening 114. Alternatively, two or more of the ferrules 125 may bebiased by a common spring. In other implementation, however, multipleferrules 125 can mount in a common opening 114. In certain examples,portions of the ferrules 125 protrude forwardly of the openings 114. Incertain examples, the ferrules 125 are laterally aligned in a row. Inother examples, the ferrules 125 can be disposed in any desired pattern.

In certain implementations, a fiber take-up arrangement 160 is disposedat the transition region 113 of the front housing 117. In someimplementations, the fiber take-up arrangement 160 includes a spool ormandrel 165. In an example, the spool 165 has a circular shape. Inanother example, the spool 165 has an oblong shape. In some examples,the spool 165 is integral with one of the housing parts 119 a, 119 b. Inother examples, the spool 165 attaches to an interior of one of thehousing parts 119 a, 119 b. In certain examples, the housing parts 119a, 119 b cooperate to define the spool 165.

In certain implementations, the anchor end 112 of the front housing 117defines a fiber passage 115 at which the optical fibers 106 may enterthe front housing 117. In examples, the fiber passage 115 is sized toreceive multiple optical fibers 106. In an example, the fiber passage115 is configured to receive one or more ribbons of optical fibers 106.In another example, the fiber passage 115 is configured to receive looseoptical fibers 106. In certain examples, the first and second housingparts 119 a, 119 b cooperate to define the fiber passage 115. The fiberpassage 115 provides access to the transition region 113 at whichindividual optical fibers 106 separate out to be terminated at theoptical ferrules 125.

In certain implementations, the anchor end 112 also includes strengthmember cavities 116 at which the strength members 107 of the multi-fibercable 105 are received. In certain examples, the first and secondhousing parts 119 a, 119 b cooperate to define the cavities 116. Inexamples, epoxy can be applied to the strength members 107 at thestrength member cavities 116 to retain the strength members 107 at theplug nose arrangement 110. In other examples, the strength members 107can be otherwise held at the cavities 116. In examples, the strengthmember cavities 116 do not connect to the transition region 113.

In certain implementations, the front housing 117 includes a reducedsection 118 at the anchor end 112. The reduced section 118 tapers orsteps inwardly from a remainder of the front housing 117. In an example,the first and second housing parts 119 a, 119 b cooperate to define thereduced section 118. In some implementations, the reduced section 118 ofthe front housing 117 defines the strength member cavities 116. Incertain implementations, the reduced section 118 of the front housing117 defines the fiber passage 115.

The coupling sleeve 130 couples to the front housing 117. In certainimplementations, the coupling sleeve 130 mounts over the reduced section118 of the front housing 117. In some implementations, the couplingsleeve 130 carries a gasket (e.g., an O-ring) 135 and includes anoutwardly extending flange 134. In the example shown, the gasket 135 isdisposed between the flange 134 and the connection end face 111. Inother implementations, the gasket 135 can be mounted within the couplingsleeve 130 or over the front housing 117. The strain-relief boot 150 iscoupled to the coupling sleeve 130 and extends over a portion of themulti-fiber cable 105.

A twist-to-lock fastener 140 is disposed over the coupling sleeve 130 toreleasably secure the optical fiber connector 100 to a component (e.g.,an optical adapter). In examples, the gasket 135 can be disposed on orin the twist-to-lock fastener 140 instead of or in addition to connectorhousing arrangement 110. In examples, the twist-to-lock fastener 140included a threadable nut having an external threaded section 142 and agripping section 145. When the connector 100 is plugged into a port of acomponent, the threaded section 142 of the twist-to-lock fastener 140 isengaged with an internal thread of the component. In other examples, thetwist-to-lock fastener 140 can include a bayonet connection. Rotatingthe twist-to-lock fastener 140 relative to the component moves thetwist-to-lock fastener 140 axially against the outwardly extendingflange 134 of the coupling sleeve 130, thereby securing the connector100 to the component.

In accordance with some aspects, during assembly of the connector 100,the multi-fiber cable 105 is threaded through the coupling sleeve 130 tothe front housing 117. The jacket is removed from a front portion of thecable 105. Strength members 107 of the cable 105 are placed in portionsof the cavities 116 defined in the first housing part 119 a of the fronthousing 117. A fiber ribbon is disposed along a portion of the fiberpassage 115 defined in the first housing part 119 a. The optical fibers106 of the ribbon are separated and terminated at the optical ferrules125. The optical ferrules 125 are mounted to the portions of theopenings 114 defined in the first housing part 119 a. Excess length ofoptical fibers 106 is wrapped around the spool 165. The second housingpart 119 b of the front housing 117 is disposed over the first housingpart 119 a to form the front housing 117. The coupling sleeve 130 slidesaxially over the reduced section 118 of the front housing 117.

FIGS. 7-11 illustrate another example optical fiber connector 200including a connector housing arrangement 210, optical ferrules 125carried by the connector housing arrangement 210, and a fiber take-uparrangement 260 disposed within the connector housing arrangement 210.The connector housing arrangement 210 defines a transition region 213.Optical fibers 206 of the multi-fiber cable 205 enter the connectorhousing arrangement 210 at the anchor end 212 and are routed through thetransition region 213 of the connector housing arrangement 210 to theoptical ferrules 125.

In some implementations, the connector housing arrangement 210 includesa front housing 217, a rear housing 219, and a coupling sleeve 230. Thefront housing 217 defines the connection end face 211 and the rearhousing 219 defines the anchor end 212 and the take-up arrangement 260.In an example, the front housing 217 includes a key 218 for rotationallyorienting the connector 200. In some implementations, the front housing217 attaches to a front of the coupling sleeve 230 and the rear housing219 attaches to a rear of the coupling sleeve 230. In certainimplementations, a portion of the rear housing 219 extends into thecoupling sleeve 230.

In some implementations, the connection end face 211 of the fronthousing 217 defines one or more openings 214 at which the opticalferrules 125 are accessible. In the example shown, each opening 214receives a connector housing 121 (e.g., an MPO connector housing)without a surrounding grip housing 127. In certain examples, eachconnector housing 121 provides a spring bias for the correspondingferrule 125. In certain examples, the connector housing 121 includes arotational orientation key. In other implementation, however, full MPOconnectors 120 including the grip housings 127 can be disposed at theopenings 214. In still other implementations, multiple connectors 120 orportions thereof can be received in an opening 214. In certain examples,portions of the ferrules 125 protrude forwardly of the openings 214. Incertain examples, the ferrules 125 are disposed in a plus sign pattern.In other examples, the ferrules 125 can be disposed in any desiredpattern.

In certain implementations, the rear housing 219 includes the anchor end212, which defines a fiber passage 215 at which the optical fibers 206may enter the connector housing arrangement 210. In examples, the fiberpassage 215 is sized to receive multiple optical fibers 206. In anexample, the fiber passage 215 is configured to receive one or moreribbons of optical fibers 206. In another example, the fiber passage 215is configured to receive loose optical fibers 206. The fiber passage 215provides access to the transition region 213 at which individual opticalfibers 206 separate out to be terminated at the optical ferrules 125.

In certain implementations, the anchor end 212 also includes strengthmember cavities 216 at which the strength members 207 of the multi-fibercable 205 are received. In examples, epoxy can be applied to thestrength members 207 at the strength member cavities 216 to retain thestrength members 207 at the connector housing arrangement 210. In otherexamples, the strength members 207 can be otherwise held at the cavities216. In examples, the strength member cavities 216 do not connect to thetransition region 213.

In certain implementations, the rear housing 219 also includes the fibertake-up arrangement 260. In some implementations, the fiber take-uparrangement 260 includes a mandrel extending forwardly of the anchorsection 212. The mandrel 265 defines axial slots 268 that provide accessto a hollow interior of the mandrel 265. Access openings 269 provideaxial access to the elongated slots 268. Excess length of optical fibers206 can be wrapped around the mandrel 265. For example, the opticalfibers 206 enter the hollow mandrel 265 through the anchor end 212. Theoptical fibers 206 can be slid through an access opening 269 into one ofthe axial slots 268 to route the optical fibers 106 to an exterior ofthe mandrel 265. The fibers 206 are wrapped around the mandrel 265 androuted towards the optical ferrules 125 at the front housing 217.

The coupling sleeve 230 couples to the front housing 217. For example,the coupling sleeve 230 can include a front fitting 231 that is sized toextend into an interior of the front housing 217 from a rear of thefront housing 217. The coupling sleeve 230 also may couple to the rearhousing 219. For example, the coupling sleeve 230 may include a rearfitting 239 that fits over the anchor end 212 of the rear housing 219.In various examples, the anchor end 212 can be glued, latched, welded,or otherwise connected to the rear fitting 239. In certain examples, themandrel 265 extends into an interior of the coupling sleeve 230. Thecoupling sleeve 230 carries a gasket 235 and includes an outwardlyextending flange 234. In certain examples, a strain-relief boot iscoupled to the coupling sleeve 230 or rear housing 219.

A twist-to-lock fastener 240 is disposed over the coupling sleeve 230 toreleasably secure the optical fiber connector 200 to a component (e.g.,an optical adapter). In examples, the twist-to-lock fastener 240included a threadable nut having an external threaded section 242 and agripping section 245. When the connector 200 is plugged into a port of acomponent, the threaded section 242 of the twist-to-lock fastener 240 isengaged with an internal thread of the component. Threading thetwist-to-lock fastener 240 to the component moves the twist-to-lockfastener 240 axially against the outwardly extending flange 234 of thecoupling sleeve 230, thereby securing the connector 200 to thecomponent.

In accordance with some aspects, during assembly of the connector 200,the cable jacket is removed from a front portion of the cable 205.Strength members 207 of the cable 205 are placed in portions of thecavities 216 at the rear housing 219. A fiber ribbon is threaded throughthe fiber passage 215 defined in the rear housing 219 and into themandrel 265. The optical fibers 206 of the ribbon are separated andterminated at the optical ferrules 125 of the connector housings 121.The connector housings 121 are disposed at the openings 214 defined inthe front housing 217. Excess length of optical fibers 206 is wrappedaround the mandrel 265 (e.g., using access openings 269 and axial slots268). The front housing 217 and the rear housing 219 mount to thecoupling sleeve 230.

FIGS. 12-16 illustrate another example optical fiber connector 300including a connector housing arrangement 310, optical ferrules 125disposed within optical connectors 120, and a fiber take-up arrangement360 disposed within the connector housing arrangement 310. In someimplementations, the optical fiber connector 300 is a female connector.For example, in certain implementations, the optical fiber connector 300includes an adapter arrangement 370 having one or more first ports 381and one or more second ports 382. The optical connectors 120 can beloaded (e.g., manually) at the first ports 381 of the adapterarrangement 370 as will be described in more detail herein. The secondports 382 face outwardly (e.g., forwardly) of the optical fiberconnector 300.

The connector housing arrangement 310 defines a transition region 313.Optical fibers 306 of the multi-fiber cable 305 enter the connectorhousing arrangement 310 at the anchor end 312 and are routed through thetransition region 313 of the connector housing arrangement 310 to theoptical ferrules 125. In some implementations, the connector housingarrangement 310 includes an inner housing 314 and a coupling sleeve 330.A strain-relief boot may couple to the inner housing 314. A coupling nut340 is disposed around and selectively engages the coupling sleeve 330.

The inner housing 314 defines the anchor end 312 and the take-uparrangement 360. The inner housing 314 also includes an outwardlyextending flange 317. In an example, the outwardly extending flangeextends radially outwardly from the anchor end 312. In certain examples,the inner housing 314 defines the connection end 311. In other examples,however, the adapter arrangement 370 can define the connection end 311.

In certain implementations, the inner housing 314 includes the anchorend 312, which defines a fiber passage 315 at which the optical fibers306 may enter the connector housing arrangement 310. In examples, thefiber passage 315 is sized to receive multiple optical fibers 306. In anexample, the fiber passage 315 is configured to receive one or moreribbons of optical fibers 306. In another example, the fiber passage 315is configured to receive loose optical fibers 306. The fiber passage 315provides access to the transition region 313 at which individual opticalfibers 306 separate out to be terminated at the optical ferrules 125.

In certain implementations, the anchor end 312 also includes strengthmember cavities 316 at which the strength members 307 of the multi-fibercable 305 are received. In examples, epoxy can be applied to thestrength members 307 at the strength member cavities 316 to retain thestrength members 307 at the connector housing arrangement 310. In otherexamples, the strength members 307 can be otherwise held at the cavities316. In examples, the strength member cavities 316 do not connect to thetransition region 313.

In some implementations, the anchor end 312 defines an axial cavity 318at the rear of the inner housing 314. Access to the fiber passage 315and strength member cavities 316 are provided at a recessed surface 319within the axial cavity 318. The jacket of the cable 305 can extend intothe axial cavity 318 to the recessed surface 319.

In certain implementations, the inner housing 314 also includes thefiber take-up arrangement 360. In some implementations, the fibertake-up arrangement 360 includes a mandrel 365 extending forwardly ofthe anchor section 312. The mandrel 365 defines axial slots 368 thatprovide access to a hollow interior of the mandrel 365. Access openings369 provide axial access to the elongated slots 368. Excess length ofoptical fibers 306 can be wrapped around the mandrel 365. For example,the optical fibers 306 enter the hollow mandrel 365 through the anchorend 112. The optical fibers 306 can be slid through an access opening369 into one of the axial slots 368 to route the optical fibers 306 toan exterior of the mandrel 365. The fibers 306 are wrapped around themandrel 365 and routed towards the optical ferrules 125.

In some implementations, the adapter arrangement 370 includes aretention wall 371 that defines one or more openings 372 at which theoptical ferrules 125 are accessible. For example, optical multi-fiberconnectors (e.g., MPO connectors) 120 may be disposed at the openings372. In the example shown, the opening 372 receives multiple opticaladapter housings (e.g., MPO adapters) 380 that each define a respectivefirst and second port 381, 382. The first port 381 of each opticaladapter housing 380 receives one of the optical multi-fiber connectors120. In examples, the connector housing 121 of each multi-fiberconnector 120 provides spring-biasing for the ferrules 125. In examples,the grip sleeves 127 of the multi-fiber connectors 120 enable a user tomanually release the connector 120 from the first port 381 of therespective adapter 380.

In certain examples, the adapters 380 (and hence the multi-fiberconnectors 120) are disposed in a plus sign pattern. In other examples,the adapters 380 and connectors 120 can be disposed in any desiredpattern. In some implementations, an optical adapter housing 380 candefine multiple first ports 381 for receiving multiple multi-fiberconnectors 120. In other implementations, the retention wall 371 definesmultiple openings 372 that each receive a separate optical adapterhousing 380.

In certain implementations, a rearward extension 373 extends outwardlyfrom the retention wall 371 towards the cable 305. A forward extension375 also extends outwardly from the retention wall 371 away from thecable 305. The forward extension 375 is configured to secure to acomponent (e.g., a male connector). For example, the forward extension375 may include a connection element (e.g., threads) 376. In an example,the forward extension 375 has a threaded inner surface.

The coupling sleeve 330 couples to the adapter arrangement 370. Incertain examples, the coupling sleeve 330 couples to the inner housing314. The coupling sleeve 330 includes a body 337 from which one or morearms 332 extend forwardly towards the adapter arrangement 370. The body337 is sized to fit around the mandrel 365. In an example, the body 337defines an axial abutment end 339 that abuts the outwardly extendingflange 317 of the inner housing 314. The coupling sleeve 330 includes anoutwardly extending flange 334 at an opposite end of the body 337 fromthe axial abutment end 339. The arms 332 extend forwardly from theoutwardly extending flange 334.

In some implementations, the forwardly extending arms 332 abut theretention wall 371 of the adapter arrangement 370. In certain examples,the forwardly extending arms 332 inhibit forward movement of thecoupling sleeve 330, which inhibits forwardly movement of the innerhousing 314. In certain examples, the forwardly extending arms 332provide stability while the optical multi-fiber connectors 120 areinserted into the first ports 381 of the adapter arrangement 370. Incertain implementations, the body 337 and the arms 332 define open sides338 through which a user can access the connectors 120 at the adapterarrangement 370. For example, the open sides 338 can extend forwardly ofthe body 337 and between the arms 332.

A twist-to-lock fastener 340 is disposed over the coupling sleeve 330 toreleasably secure the coupling sleeve 330 to the adapter arrangement370. In certain implementations, the twist-to-lock fastener 340 coversthe open sides 338 when secured to the adapter arrangement 370, therebyinhibit access to the multi-fiber connectors 120. In certainimplementations, the twist-to-lock fastener 340 carries a gasket (e.g.,an internal O-ring, an external O-ring, an axial seal, etc.) that abutsagainst the outwardly extending flange 317. In some implementations, thetwist-to-lock fastener 340 carries a gasket (e.g., an internal O-ring,an external O-ring, etc.) that mates with the rearward extension 373 ofthe adapter arrangement 370. In other implementations, the gasket iscarried by the rearward extension 373 and seals to the twist-to-lockfastener 340 when the twist-to-lock fastener 340 is secured to theadapter arrangement 370.

In some implementations, the twist-to-lock fastener 340 included athreadable nut having a threaded section 342 and a gripping section 345.In the example shown, the threaded section 342 is an internal threadedsection and the gripping section 345 is an external gripping section.The threaded section 342 of the twist-to-lock fastener 340 engages aconnection element 374 (e.g., an external thread) of the rearwardextension 373. In other implementations, the twist-to-lock fastener 340can have a bayonet connection. Threading or otherwise twisting thetwist-to-lock fastener 340 relative to the adapter arrangement 370 movesthe twist-to-lock fastener 340 axially against the outwardly extendingflange 334 of the coupling sleeve 330, thereby securing the couplingsleeve 330 to the adapter arrangement 370.

In accordance with some aspects, during assembly of the connector 300, ajacketed portion of the cable 305 is inserted into the axial cavity 318.Strength members of the cable 305 are placed in the cavities 316; afiber ribbon is threaded through the fiber passage 315 and into themandrel 365. The optical fibers 306 of the ribbon are separated andterminated at the optical ferrules 125 of the multi-fiber connectors120. The multi-fiber connectors 120 are plugged into the first ports 381of the optical adapter housings 380 at the adapter arrangement 370.Excess length of optical fibers 306 is wrapped around the mandrel 365(e.g., using access openings 369 and axial slots 368).

FIGS. 17-30 illustrate yet another example optical fiber connector 400including a connector housing arrangement 410, optical ferrules 425carried by the connector housing arrangement 410, and a fiber take-uparrangement 460 disposed within the connector housing arrangement 410.The connector housing arrangement 410 defines a transition region 413.Optical fibers 406 of the multi-fiber cable 405 enter the connectorhousing arrangement 410 at the anchor end 412 and are routed through thetransition region 413 of the connector housing arrangement 410 to theoptical ferrules 425.

In some implementations, the connector housing arrangement 410 includesa front housing 417 and a coupling sleeve 430. The front housing 417defines the connection end face 411, the anchor end 412, and the take-uparrangement 460. In some implementations, the front housing 417 includesan integral housing. In other implementations, however, the fronthousing 417 includes a first housing section 419 a and a second housingsection 419 b. In certain examples, the first and second housing parts419 a, 419 b cooperate to retain the ferrules 425. In certain examples,the first and second housing parts 419 a, 419 b surround and protect thetake-up arrangement 460. In an example, the first and second housingparts 419 a, 419 b latch together.

In some implementations, the connection end face 411 of the fronthousing 417 defines one or more openings at which the optical ferrules425 are accessible. For example, one or both housing parts 419 a, 419 bmay define open-ended slots or notches 414. In an example, both housingparts 419 a, 419 b define open-ended notches 414 that align with eachother. In another example, the first housing 419 a defines theopen-ended notches 414 and the second housing 419 b defines a wall orother surface that closes the notches 414.

In the example shown, each ferrule 425 mounts in a respective one of theopenings. For example, each ferrule 425 may include a shoulder 426 (FIG.19) that abuts a retention surface at the notch 414 (see FIG. 21). Incertain examples, the ferrules 425 are laterally aligned in a row. Inother examples, the ferrules 425 can be disposed in any desired pattern.Each ferrule 425 may be individually spring-biased within the respectiveopening. In an example, each ferrule 425 can be biased by a coil spring.In another example, each ferrule 425 can be biased by a low profile leafspring. Alternatively, two or more of the ferrules 425 may be biased bya common spring (e.g., coil spring, leaf spring, etc.). In otherimplementation, however, the ferrules 425 are not spring-biased.

In some implementations, portions of the ferrules 425 protrude forwardlyof the connection end face 411 (see FIG. 17). In certainimplementations, one or more flanges 402 extend forwardly of theconnection end face 411 (see FIG. 17). In certain examples, the flanges402 extend forwardly past the ferrules 425 (see FIGS. 21 and 22). Incertain examples, the flanges 402 form an interrupted wall extendingforwardly of the connection end face 411. For example, interruptions 403in the wall may provide access to the ferrules 425 for cleaning and/orpolishing.

In certain implementations, a fiber take-up arrangement 460 is disposedat the transition region 413 of the front housing 417. In someimplementations, the fiber take-up arrangement 460 includes a spool ormandrel 465. In an example, the spool 465 has a circular shape. Inanother example, the spool 465 has an oblong shape. In some examples,the spool 465 is integral with one of the housing parts 419 a, 419 b. Inother examples, the spool 465 attaches to an interior of one of thehousing parts 419 a, 419 b. In certain examples, the housing parts 419a, 419 b cooperate to define the spool 465. In certain examples, one ormore flanges 467 may extend radially outwardly from the spool 465 to aidin retaining and/or managing the optical fibers 406. In an example, eachflange 467 may have an anchor end inserted into a hole 466 in the spool465 (see FIG. 20).

In certain implementations, the anchor end 412 of the front housing 417defines a fiber passage 415 at which the optical fibers 406 may enterthe front housing 417. The fiber passage 415 provides access to thetransition region 413 at which individual optical fibers 406 separateout to be terminated at the optical ferrules 425. In examples, the fiberpassage 415 is sized to receive multiple optical fibers 406. In anexample, the fiber passage 415 is configured to receive one or moreribbons of optical fibers 406. In another example, the fiber passage 415is configured to receive loose optical fibers 406. In some examples, thefirst and second housing parts 419 a, 419 b cooperate to define thefiber passage 415. In other examples, the first housing part 419 adefines the anchor end 412 and fiber passage 415.

In certain implementations, the anchor end 412 also includes strengthmember cavities 416 at which the strength members 407 of the multi-fibercable 405 are received. In some examples, the first and second housingparts 419 a, 419 b cooperate to define the cavities 416. In otherexamples, however, the first housing part 419 a includes the anchor end412 that defines the cavities 416. In examples, epoxy can be applied tothe strength members 407 at the strength member cavities 416 to retainthe strength members 407 at the connector housing arrangement 410. Inother examples, the strength members 407 can be otherwise held at thecavities 416. In examples, the strength member cavities 416 do notconnect to the transition region 413.

In accordance with some aspects, during assembly of the connector 400,the multi-fiber cable 405 is threaded through the coupling sleeve 430 tothe front housing 417. The jacket is removed from a front portion of thecable 405. Strength members 407 of the cable 405 are placed in portionsof the cavities 416 defined in the anchor end 412. A fiber ribbon isdisposed along a portion of the fiber passage 415 defined in the firsthousing part 419 a. The optical fibers 406 of the ribbon are separatedand terminated at the optical ferrules 425. The optical ferrules 425 aremounted at the notches 414 defined in the first housing part 419 a.Excess length of optical fibers 406 is wrapped around the spool 465 (seeFIG. 21). The second housing part 419 b of the front housing 417 isdisposed over the first housing part 419 a to form the front housing417.

In certain implementations, the front housing 417 includes a reducedsection 418 at the anchor end 412. The reduced section 418 tapers orsteps radially inwardly from an outer periphery of the front housing417. In some examples, the first and second housing parts 419 a, 419 bcooperate to define the reduced section 418. In other examples, thefirst housing part 419 a defines the reduced section 418. In someimplementations, the reduced section 418 of the front housing 417defines the strength member cavities 416. In certain implementations,the reduced section 418 of the front housing 417 defines the fiberpassage 415.

The coupling sleeve 430 couples to the front housing 417. In certainimplementations, the coupling sleeve 430 mounts over the reduced section418 of the front housing 417 (see FIGS. 21 and 22). In an example, thecoupling sleeve 430 is rotationally keyed to the reduced section 418(e.g., by respective flats 418 a, 436 shown in FIG. 18). In someimplementations, the coupling sleeve 430 carries a gasket (e.g., anO-ring) 435 and includes an outwardly extending flange 434. In theexample shown, the gasket 435 is disposed between the flange 434 and theconnection end face 411. In other implementations, the gasket 435 can bemounted within the coupling sleeve 430 or over the front housing 417.

The strain-relief boot 450 is coupled to the coupling sleeve 430 (e.g.,over the heat recoverable sleeve 455) and extends over a portion of themulti-fiber cable 405 (see FIG. 21). In certain examples, the couplingsleeve 430 includes a reduced section 437 over which a portion of thestrain-relief boot 450 extends. In certain examples, the reduced section437 of the coupling sleeve 430 includes a textured surface (e.g., ribs,threads, bumps, etc.) that facilitates attaching the heat recoverablesleeve 435. In certain examples, the reduced section 437 defines agroove or slots into which a ledge or teeth of the strain-relief boot450 extend to hold the strain-relief boot 450 to the coupling sleeve430.

In certain implementations, the coupling sleeve 430, the heatrecoverable sleeve 455, and/or the strain-relief boot 450 are shaped tomatch an outer periphery of the cable 405. For example, in someimplementations, the cable 405 is a flat cable. In such cases, thecoupling sleeve 430, the heat recoverable sleeve 455, and/or thestrain-relief boot 450 have a flattened profile corresponding to thecable 405 (see FIG. 18). In other implementations, the cable 405 is around cable. In such cases, the coupling sleeve 430, the heatrecoverable sleeve 455, and/or the strain-relief boot 450 have a roundedprofile corresponding to the cable 405 (see FIG. 18A).

A twist-to-lock fastener 440 is disposed over the coupling sleeve 430 toreleasably secure the optical fiber connector 400 to a component (e.g.,an optical adapter). In examples, the gasket 435 can be disposed on orin the twist-to-lock fastener 440 instead of or in addition to connectorhousing arrangement 410. In examples, the twist-to-lock fastener 440included a threadable nut having an external threaded section 442 and agripping section 445. When the connector 400 is plugged into a port of acomponent, the threaded section 442 of the twist-to-lock fastener 440 isengaged with an internal thread of the component. In other examples, thetwist-to-lock fastener 440 can include a bayonet connection. Rotatingthe twist-to-lock fastener 440 relative to the component moves thetwist-to-lock fastener 440 axially against the outwardly extendingflange 434 of the coupling sleeve 430, thereby securing the connector400 to the component.

FIGS. 23-30 illustrate example components to which the connector 400 canbe secured. FIGS. 23-24 illustrate an example dust cap 470 that securesto the connector 400 to cover the connection end face 411. The dust cap470 has a body 471 extending from an open end 472 to a closed end 473.The dust cap body 471 defines a hollow interior 474 accessible throughthe open end 472. The dust cap body 471 defines a fastening region thatis configured to engage with the twist-to-lock fastener 440. Forexample, the dust cap body 471 may define internal threading 475 at thefirst end 472.

In use, the front housing 417 of the connector 400 is inserted into theinterior 474 of the dust cap 470. The ferrules 425 are protected by theclosed end 473 and the body 471. In certain examples, the gasket 435 ofthe connector 400 presses against the interior surface of the dust capbody 471 to environmentally seal the ferrules 425 within the dust cap470. In certain examples, the closed end 473 includes a pulling eye 476that enables the cable 405 to be pulled through a conduit or otherpassage.

FIGS. 25-30 illustrate an example optical adapter 500 defining a port atwhich the optical connector 400 can be received. In someimplementations, the optical adapter 500 includes a body 501 thatextends from a first end 502 to a second end 503. The first end 501defines the port sized to receive the optical connector 400. In someimplementations, the second end 502 of the body 501 is configured tosupport optical ferrules 525 that mate with the optical ferrules 425 ofthe connector 400. In other implementations, the second end 502 of thebody 501 defines a second port that can receive an optical connector.

The adapter body 501 includes a flange 504 that extends radiallyoutwardly from the body 501. The adapter body 501 defines externalthreads 505 adjacent the flange 504. The adapter 500 includes aretaining ring 540 that is configured to move axially along the adapterbody 501. For example, in one implementation, the retaining ring 540 hasan internal thread 541 that engages the external threads 505 of theadapter body 501. In certain examples, the retaining ring 540 definesexternal notches 542 that facilitate rotating the retaining ring 540.

The retaining ring 540 cooperates with the flange 504 to secure a wall,panel, or other surface therebetween to mount the adapter 500 to thewall, panel, or other surface. In some implementations, the flange 504is disposed at the first end 502 of the body 501. In otherimplementations, flange 504 is disposed closer to the second end 503 ofthe body 501. In still other implementations, the flange 504 is disposedat any intermediate position between the first and second ends 502, 503.

As shown in FIG. 26, the adapter body 501 includes internal fasteningfeatures 506 at the first end 502. The internal fastening features 506are configured to engage with the twist-to-lock fastener 440 of theconnector 400 to hold the connector 400 at the adapter 500. In someimplementations, the internal fastening features 506 include internalthreading (see FIG. 26). In other implementations, the internalfastening features 506 include part of a bayonet connection. The adapterbody 501 also includes a sealing surface 507 against which the gasket435 of the connector 400 presses when the connector 400 is disposedwithin the adapter 500. Accordingly, the front housing 417 of theconnector 400 can be environmentally sealed within the adapter 500.

As shown in FIGS. 26-28, the adapter body 501 includes an internal wall510 at which adapter ferrules 525 can be disposed. The internal wall 510defines openings 512 through which the adapter ferrules 525 extend withend faces 526 of the ferrules 525 facing towards the first end 502 ofthe adapter body 501. When the connector 400 is disposed at the adapter500, the connection end face 411 of the connector 400 abuts or isdisposed adjacent to the internal wall 510. The optical ferrules 425 ofthe connector 400 align with the optical ferrules 525 of the adapter500. When the twist-to-lock fastener 440 of the connector 400 is engagedwith the internal fastening feature 506 of the adapter, the opticalferrules 425, 525 optically couple together (e.g., see FIG. 30).

A first interior region of the adapter body 501 extending from theinternal wall 510 to the first end 502 of the adapter body 501 isconfigured to receive the connector 400. For example, in certainimplementations, the internal wall 510 defines depressions 511 sized andshaped to accommodate the forwardly extending flanges 402 of theconnector 400. The depressions 511 enable the connection end face 411 ofthe connector 400 to approach and/or abut the internal wall 510 of theadapter 500.

In certain implementations, an inner surface of the first interiorregion of the adapter body 501 defines one or more axially extendingkeyways 509. The keyways 509 are sized and shaped to accommodate axiallyextending keys 409 (FIGS. 17 and 19) on the connector 400. The keys 409and keyways 509 rotationally orient the connector 400 relative to theadapter 500 when the connector 400 is inserted at the adapter port. Thekeys 409 and keyways 509 also maintain the rotational orientation of theconnector 400 relative to the adapter 500 as the connector 400 continuesto be inserted into the adapter 500 and the ferrules 425, 525 align.

A second interior region of the adapter body 501 extending from theinternal wall 510 to the second end 503 of the adapter body 501 isconfigured to receive an adapter ferrule arrangement 520. The adapterferrule arrangement 520 includes one or more adapter ferrules (e.g.,multi-fiber ferrules) 525 and optical fibers 529 extending outwardlyfrom the adapter ferrules 525. The adapter ferrule arrangement 520 alsocan include one or more ferrule springs (e.g., coil springs, leafsprings, etc.) 528. In an example, each adapter ferrule 525 has acorresponding ferrule spring 528. In another example, one ferrule spring528 can bias multiple of the adapter ferrules 525.

In some implementations, the second interior region defines a cavity 515in which the adapter ferrule arrangement 520 is disposed (see FIG. 27).A ferrule plug 530 is inserted into the cavity 515 to retain the adapterferrule arrangement 520 between the ferrule plug 530 and the internalwall 510 (see FIGS. 26 and 30). The ferrule plug 530 defines a cavity535 in which the adapter ferrule arrangement 520 is at least partiallydisposed (see FIG. 26). The cavity 535 is open at a first end 531 of theferrule plug 530 (FIG. 29). A second end 532 of the ferrule plug 530includes an end surface 536 that defines openings 537 through which thefibers 529 of the adapter ferrule arrangement 520 extend (See FIG. 31).The springs 528 are disposed between the end surface 536 and the adapterferrules 525 to bias the ferrules 525 through the internal wall openings512.

Referring to FIGS. 27 and 29, the ferrule plug 530 includes an outerwall 533 that extends axially from a first end 531 to a second end 532.In an example, the outer wall 533 is an annular wall. The outer wall 533includes one or more latching arms 534 that each have a latching hookthat protrudes radially outwardly from the outer wall 533. The latchingarms 534 flex to displace the latching hooks radially inwardly relativeto the outer wall 533. The adapter body 501 defines latch openings 516sized to receive the latching hooks on the latching arms 534. The latchopenings 516 are located between the internal wall 510 and the secondend 503 of the adapter body 501. Guide channels 517 can lead from thesecond end 503 to the latch openings 516 (see FIG. 27).

In certain implementations, the internal wall 510 and the ferrule plug530 include alignment features that rotationally orient the ferrule plug530 within the adapter cavity 515. Accordingly, the ferrules 525, endsurface openings 537 of the ferrule plug 530, and internal wall openings512 of the adapter body 501 will align. In some implementations, theadapter internal wall 510 includes alignment members 518 that extendtowards the second end 503 of the adapter body 501. The ferrule plug 530defines alignment holes 538 that are sized and shaped to receive thealignment members 518 of the internal wall 510 when the ferrule plug 530is received at the adapter cavity 515. In other examples, however, theadapter internal wall 510 can define alignment holes and the ferruleplug 530 can define alignment members.

FIGS. 31 and 32 illustrate an example adapter dust plug 550 that isconfigured to be received in the port at the first end 502 of theadapter body 501. The adapter dust plug 550 includes a plug body 551that fits within the first interior region of the adapter 500. One ormore plug members 553 extend forwardly from a connection end face of theplug body 551. The plug members 553 protect the end faces 526 of theadapter ferrules 525. The number of plug members 553 corresponds to thenumber of adapter ferrules 525 within the adapter body 501. In someimplementations, the plug members 553 are sized to extend into openings512 to engage the adapter ferrules 525. In other implementations, aconnection end face of the plug body 551 does not include plug members553.

In certain implementations, the plug body 551 includes axially extendingkeys 552. The keys 552 cooperate with the keyways 509 within the adapterbody 501 to rotationally orient the adapter dust plug 550 relative tothe adapter 500 when the adapter dust plug 550 is inserted at theadapter port. The keys 552 and keyways 509 also maintain the rotationalorientation of the adapter dust plug 550 relative to the adapter 500 asthe adapter dust plug 550 continues to be inserted into the adapter 500and the plug members 553 engage the ferrules 525.

In some implementations, the adapter dust plug 550 includes atwist-to-lock fastener 559 that engages the internal fastening features506 of the adapter body 501 to hold the adapter dust plug 550 at theadapter 500. For example, the twist-to-lock fastener 559 can includeexternal threads or a bayonet connection. The twist-to-lock fastener 559is configured to rotate relative to the plug body 551. Accordingly, theadapter dust plug 550 can be secured to the adapter 500 without movementof the plug members 553 relative to the adapter ferrules 525, whichcould otherwise damage the adapter ferrules 525 and/or plug members 553.

As shown in FIG. 32, the adapter dust plug 550 includes a separatefastener body 557 that carries the twist-to-lock fastener 559. Thefastener body 557 also can include a grip section 562 configured tofacilitate grasping by a user for manipulation of the fastener body 557.For example, the grip section 562 can step radially outwardly from thetwist-to-lock fastener 559. In certain examples, the grip section 562can include flats 563 around an outer perimeter.

The fastener body 557 is configured to be mounted to the plug body 551at an axially fixed position. The fastener body 557 can rotate relativeto the plug body 551. In certain examples, the fastener body 557 canrotate freely relative to the plug body 551. For example, in certainimplementations, an attachment feature 554 extends from the plug body551 opposite the connection end face. The attachment feature 554includes flexible members 555 configured to deflect inwardly. Eachflexible member 555 includes an outwardly extending latch member 556.

The attachment feature 554 can fit within an interior passage 558 of thefastener body 557. An inner surface of the passage 558 can define anannular channel. The latch members 556 deflect inwardly as theattachment feature 554 is slid into the fastener body 557. When thelatch members 556 reach the inner annular channel, the latch members 556deflect into the channel to hold the plug body 551 at an axially fixedposition relative to the fastener body 557. The plug body 551 can rotaterelative to the fastener body 557 by allowing the latch members 556 toslide along the annular channel.

In certain implementations, the adapter dust plug 550 is configured toenvironmentally seal to the adapter 500. For example, a gasket (e.g.,O-ring) 565 can be disposed on the fastener body 557 so that the gasket565 is disposed within the adapter body 501 at the sealing surface 507when the adapter dust plug 550 is received at the adapter 500. Incertain implementations, the fastener body 557 includes a supportsection 560 over which the gasket 565 is mounted. A radial step 561transitions between the support section 560 and the twist-to-lockfastener 559.

FIGS. 33-43 illustrate yet another example optical fiber connectorarrangement 600 for a multi-fiber cable 605. The optical fiber connectorarrangement 600 includes a connector housing arrangement 610 and a fibertake-up arrangement 660 spaced along the multi-fiber cable 605 from theconnector housing arrangement 610. The multi-fiber cable 605 is anchoredto the fiber take-up arrangement 660 and excess length of optical fibers606 of the multi-fiber cable 605 is stored at a storage drum 662therein. Distal ends of the optical fibers 606 are routed through afurcation cable 695 to the connector housing arrangement 610. A firstend of the furcation cable 695 is anchored to the fiber take-uparrangement 660. A second end of the furcation cable 695 is anchored tothe connector housing arrangement 610. The distal ends of the opticalfibers 606 are connectorized at the ferrules 625 and disposed at aconnection end 611 of the connector housing arrangement 610.

FIGS. 34-37 illustrate one example fiber take-up arrangement 660suitable for use in the optical fiber connector arrangement 600. Thefiber take-up arrangement 660 includes a mandrel arrangement 661 and asealing arrangement 670. The mandrel arrangement 661 is configured tohold the excess length of the optical fibers 606. The mandrelarrangement 661 also is configured to anchor the strength members 607 ofthe multi-fiber cable 605 and the strength members 697 of the furcationcable 695. The sealing arrangement 670 provides an environmentally sealbetween the multi-fiber cable 605 and the furcation cable 695.

The mandrel arrangement 661 includes a first anchor body 663 a separatedfrom a second anchor body 663 b by a gap. A drum 662 extends across thegap to connect the first and second anchor bodies 663 a, 663 b. In anexample, the drum 662 has a circular shape. In another example, the drum662 has an oblong shape. Optical fibers 606 of the multi-fiber cable 605extend axially between the anchor bodies 663 a, 663 b to the drum 662,wrap around the drum 662, and extend axially between the anchor bodies663 a, 663 b away from the drum 662. The drum 662 is sized to inhibitexcessive bending of the optical fibers 662 wrapped therearound.

In some implementations, the anchor bodies 663 a, 663 b of the mandrelarrangement 661 are configured to axially fix the strength members 607,697 of the cable 605, 695. In certain implementations, each anchor body663 a, 663 b is configured to axially fix a strength member 607, 697 ofeach cable 605, 695. In certain examples, the strength members 607, 697are terminated at anchor boots 609, 699, respectively. The anchor bodies663 a, 663 b are configured to receive and axially retain the anchorboots 609, 699. In examples, each anchor body 663 a, 663 b defines achannel 667 that extends from an axial end of the anchor body 663 a, 663b to a cavity 668 defined at an intermediate location along the anchorbody 663 a, 663 b.

In certain examples, the anchor boots 609, 699 are shaped to match theshape of the cavities 668. In the example shown, the anchor boots 609,699 have T-shaped axial cross-sections that match the T-shaped axialcross-sections of the cavities 668. In certain examples, the anchorboots 609, 699 and cavities 668 are shaped to enable the anchor boots609, 699 to pass laterally (i.e., radially) into the cavities 668 whileinhibiting axial movement of the anchor boots 609, 699 relative to thecavities 668. The strength members 607, 697 of the cables 605, 695 aredisposed within the channels 667 when the anchor boots 609, 699 aredisposed in the cavities 668.

In certain implementations, the anchor bodies 663 a, 663 b reduce incross-section at the axial ends. These axial end sections 665, 666define mounting surfaces for the sealing arrangement 670. For example,each axial end section 665, 666 may define external threads 665 a, 666a. In some implementations, the threads 665 a, 666 a are spaced inwardlyfrom the axial ends of the anchor bodies 663 a, 663 b (see FIG. 35). Inother implementations, the threads 665 a, 666 a are disposed at theaxial ends of the anchor bodies 663 a, 663 b. In some examples, theaxial end sections 665, 666 define portions of the channels 667. Inother examples, the channels 667 extend across the larger intermediatesections of the anchor bodies 663 a, 663 b.

The sealing arrangement 670 includes a closure member 672 configured tosurround the mandrel arrangement 661. The closure member 672 extendsover the cavities 668, thereby retaining the anchor boots 609, 699 inthe cavities 668. First and second end members 674 mount to oppositeends of the mandrel arrangement 661 to hold the closure member 372therebetween. For example, each of the first and second end members 674may define internal threads 676 that engage the external threads 665 a,666 a at a respective axial end section 665, 666. The closure member 672is axially held between the first and second end members 674. Forexample, each of the first and second end members 674 may flare or stepradially outwardly at the axial end facing the closure member 672.

Each of the opposite axial ends of the closure member 672 defines anattachment section 673. For example, the attachment sections 673 canstep or taper radially inwardly from an intermediate section of theclosure member 672. Portions of the first and second end members 674extend over the attachment sections 673. For example, each end member674 can include a sealing surface 675 that extends over the respectiveattachment section 673. Seals (e.g., O-rings) 679 can be disposedbetween the attachment sections 673 and the sealing surfaces 675 (seeFIG. 36). In some implementations, the seals 679 are compressed radiallybetween the attachment sections 673 and the sealing surfaces 675. Inother implementations, the seals 679 are compressed axially between theclosure member 661 and the respective end members 673.

The sealing arrangement 670 also is configured to seal to the cables605, 695. For example, the first and second end members 674 may includemounting sections 677 opposite the sealing surfaces 675. A heatrecoverable sleeve 678 can have a first portion extending over a jacket608, 698 of the cable 605, 695 and a second portion extend over themounting section 677 of the respective end member 674. In certainexamples, the mounting sections 677 can be textured (e.g., ribs,threads, bumps, etc.) to aid in axially retention of the heatrecoverable sleeve 678.

FIGS. 38-43 illustrate the example connector housing arrangement 610that couples to the furcation cable 695. The connector housingarrangement 610 holds the optical ferrules 625 at the connection end611. Optical fibers 606 of the multi-fiber cable 605 (or furcationfibers optically coupled to the optical fibers 606) enter the connectorhousing arrangement 610 at an anchor end 612, extend through atransition region 613, and terminate at the optical ferrules 625.

In some implementations, the connector housing arrangement 610 includesa front housing 617 and a coupling sleeve 630. The front housing 617defines the connection end face 611, a ferrule mounting region 614, andthe anchor end 612. In some implementations, the front housing 617includes an integral housing. In other implementations, however, thefront housing 617 includes a first housing section 619 a (FIG. 40) and asecond housing section 619 b (FIG. 41). The first and second housingsections 619 a, 619 b can include alignment members to properly positionthe housing sections 619 a, 619 b. For example, the first and secondhousing sections 619 a, 619 b can include mating tabs 620 a and slots620 b. In certain examples, the housing sections 619 a, 619 b latchtogether. In certain examples, the housing sections 619 a, 619 b areheld together by the coupling sleeve 630.

The front housing 617 is elongated between the connection end 611 andthe anchor end 612. The coupling sleeve 630 is configured to extendaround the front housing 617 over a majority of the length of the fronthousing 617 (see FIGS. 42-43). The interior surface of the couplingsleeve 630 generally follows the exterior surface of the front housing617. The coupling sleeve 630 is sized to retain the housing sections 619a, 619 b of the front housing 617 together when the coupling sleeve 630is mounted about the front housing 617.

In some implementations, a front portion of the front housing 617 stepsradially outwardly to define a rear facing shoulder 621. A first end 631of the coupling sleeve 630 faces the rear facing shoulder 621 when thecoupling sleeve 630 is mounted about the front housing 617. In certainexamples, the first end 631 of the coupling sleeve 630 abuts the rearfacing shoulder 621. The interaction between the shoulder 621 and thefirst end 631 inhibits further forward movement of the coupling sleeve630 over the front housing 617. A groove 623 is defined at a rear of thefront housing 617 (see FIG. 39). The coupling sleeve 630 includes a hook639 configured to mate with the groove 623 when the coupling sleeve 630is mounted about the front housing 617 (see FIG. 43). In an example, thehook 639 is inwardly flexible relative to the front housing 617. Theinteraction between the hook 639 and the groove 623 inhibits furtherrearward movement of the coupling sleeve 630 over the front housing 617.

In certain implementations, one or more flanges 602 extend forwardly ofthe connection end face 611 (see FIG. 38). In certain examples, theflanges 602 extend forwardly past the ferrules 625. In certain examples,the flanges 602 form an interrupted wall extending forwardly of theconnection end face 611. For example, interruptions 603 in the wall mayprovide access to the ferrules 625 for cleaning and/or polishing. Insome implementations, the flanges 602 are integral with the fronthousing 617. In other implementations, the flanges 602 are integral withthe coupling sleeve 630.

In some implementations, the coupling sleeve 630 carries a gasket (e.g.,an O-ring) 635 and includes an outwardly extending flange 634. In theexample shown, the gasket 635 is disposed between the flange 634 and theconnection end face 611. In other implementations, the gasket 635 can bemounted within the coupling sleeve 630 or over the front housing 617.

The connector housing arrangement 610 also is configured to seal to thefurcation cable 695. In certain examples, the coupling sleeve 630includes a reduced section 637 over which a portion of a strain-reliefboot 650 extends. In some implementations, the strain-relief boot 650provides side load strain relief to the furcation cable 695. In certainimplementations, a heat recoverable sleeve 655 has a first portionextending over a jacket 698 of the furcation cable 695 and a secondportion extend over a reduced section 637 of the coupling sleeve 630. Incertain examples, the rear 637 of the coupling sleeve 630 can betextured (e.g., ribs, threads, bumps, etc.) to aid in axially retentionof the heat recoverable sleeve 655.

The strain-relief boot 650 is coupled to the coupling sleeve 630 (e.g.,over the heat recoverable sleeve 655) and extends over a portion of thefurcation cable 695 (see FIGS. 42 and 43). In certain examples, thereduced section 637 defines a groove or slot 638 into which a ledge 655or teeth of the strain-relief boot 650 extend to hold the strain-reliefboot 450 to the coupling sleeve 630 (see FIGS. 42 and 43). In certainimplementations, the coupling sleeve 630, the heat recoverable sleeve655, and/or the strain-relief boot 650 are shaped to match an outerperiphery of the furcation cable 695. For example, in someimplementations, the furcation cable 405 is a flat cable. In such cases,the coupling sleeve 630, the heat recoverable sleeve 655, and/or thestrain-relief boot 650 have a flattened profile corresponding to thefurcation cable 695. In other implementations, the furcation cable 695is a round cable. In such cases, the coupling sleeve 630, the heatrecoverable sleeve 655, and/or the strain-relief boot 650 have a roundedprofile corresponding to the furcation cable 695.

In some implementations, the connection end face 611 of the fronthousing 617 defines one or more openings 614 a at which the opticalferrules 625 are accessible. In certain examples, the first and secondhousing parts 619 a, 619 b cooperate to retain the ferrules 625. Forexample, the housing parts 619 a, 619 b may define open-ended slots ornotches 614 a that align with each other to form openings in which theferrules 625 are disposed. In another example, a retainer 624 (FIG. 39)is disposed between the notches 614 a defined by the first housing part619 a and the notches 614 a defined by the second housing part 619 b(see FIG. 42).

In the example shown, each ferrule 625 mounts in a respective one of theopenings 614 a. For example, each ferrule 625 may include a shoulder 626that abuts a retention surface at the notch 614 a (see FIG. 43). In someimplementations, portions of the ferrules 625 protrude forwardly of theconnection end face 611. Each ferrule 625 may be individuallyspring-biased within the respective opening. In an example, each ferrule625 can be biased by a spring (e.g., a coil spring, a leaf spring, etc.)627 disposed in a cavity 614 b. One end of the spring 627 abuts a springretention surface 614 c and the opposite end of the spring 627 abuts theferrule 625 (see FIGS. 42-43). Alternatively, two or more of theferrules 625 may be biased by a common spring (e.g., coil spring, leafspring, etc.). In other implementation, however, the ferrules 625 arenot spring-biased.

In certain implementations, the anchor section 612 of the front housing617 defines a fiber passage 615 at which the optical fibers 606 extendthrough the anchor section 612. The fiber passage 615 provides access toa transition region 613 at which individual optical fibers 606 separateout to be terminated at the optical ferrules 625. In examples, the fiberpassage 615 is sized to receive multiple optical fibers 606. In anexample, the fiber passage 615 is configured to receive one or moreribbons of optical fibers 606. In another example, the fiber passage 615is configured to receive loose optical fibers 606. In some examples, thefirst and second housing parts 619 a, 619 b cooperate to define thefiber passage 615. In other examples, the first housing part 619 adefines the fiber passage 615.

In certain implementations, the anchor end 612 also includes strengthmember cavities 616 a at which the strength members 697 of the furcationcable 695 are received. In some examples, the first and second housingparts 619 a, 619 b cooperate to define the cavities 616 a. In otherexamples, however, the first housing part 619 a defines the cavities 616a and the second housing part 619 b includes surfaces 616 b that closethe cavities 616 a. In examples, anchor boots 699 can be attached to thestrength members 695 of the furcation cable 695 and laterally insertedinto the cavities 616 a. Interaction between the anchor boots 699 andretaining walls at the cavities 616 a axially retain the strengthmembers 697 against pulling out of the front housing 617. In certainexamples, epoxy can be applied to the strength members 697 and/or anchorboots 699 at the strength member cavities 616 a. In other examples, thestrength members 697 can be otherwise held at the cavities 616 a. Inexamples, the strength member cavities 616 a do not connect to thetransition region 613.

A twist-to-lock fastener 640 is disposed over the coupling sleeve 630 toreleasably secure the optical fiber connector arrangement 600 to acomponent (e.g., an optical adapter). In examples, the gasket 635 can bedisposed on or in the twist-to-lock fastener 640 instead of or inaddition to connector housing arrangement 610. In examples, thetwist-to-lock fastener 640 included a threadable nut having an internalthreaded section 642 and a gripping section 645. When the connectorarrangement 600 is plugged into a port of a component, the threadedsection 642 of the twist-to-lock fastener 640 is engaged with anexternal thread of the component. In other examples, the twist-to-lockfastener 640 can include a bayonet connection. Rotating thetwist-to-lock fastener 640 relative to the component moves thetwist-to-lock fastener 640 axially against the outwardly extendingflange 634 of the coupling sleeve 630, thereby securing the connectorarrangement 600 to the component.

FIGS. 44-49 illustrate an example optical adapter 700 defining a port atwhich the optical connector arrangement 600 can be received. In someimplementations, the optical adapter 700 includes a body 701 thatextends from a first end 702 to a second end 703. The first end 701defines the port sized to receive the optical connector arrangement 600.In some implementations, the second end 702 of the body 701 isconfigured to support optical ferrules 725 that mate with the opticalferrules 625 of the connector arrangement 600. In other implementations,the second end 702 of the body 701 defines a second port that canreceive an optical connector.

The adapter body 701 includes a fastening feature 706 at the first end702. The fastening feature 706 is configured to engage with thetwist-to-lock fastener 640 of the connector arrangement 600 to hold theconnector arrangement 600 at the adapter 700. In some implementations,the fastening feature 706 includes external threading (see FIG. 45). Inother implementations, the fastening features 706 include part of abayonet connection. The adapter body 701 also includes a sealing surface711 against which the gasket 635 of the connector arrangement 600presses when the connector arrangement 600 is disposed within theadapter 700. Accordingly, the front housing 617 of the connectorarrangement 600 can be environmentally sealed within the adapter 700.

The adapter body 701 includes a flange 704 that extends radiallyoutwardly from the body 701. The adapter body 701 defines externalthreads 705 adjacent the flange 704. In certain implementations, theflange 704 is disposed between the fastening feature 706 and theexternal threads 705. The adapter 700 includes a retaining ring 740 thatis configured to move axially along the adapter body 701. For example,in one implementation, the retaining ring 740 has an internal thread 741that engages the external threads 705 of the adapter body 701. Incertain examples, the retaining ring 740 defines external notches 742that facilitate rotating the retaining ring 740. The retaining ring 740cooperates with the flange 704 to secure a wall, panel, or other surfacetherebetween to mount the adapter 700 to the wall, panel, or othersurface. In some implementations, the flange 704 is disposed at thefirst end 702 of the body 701. In other implementations, flange 704 isdisposed closer to the second end 703 of the body 701. In still otherimplementations, the flange 704 is disposed at any intermediate positionbetween the first and second ends 702, 703.

As shown in FIGS. 45-47, the adapter body 501 is configured to receive aferrule plug 730 that holds the optical ferrules 725. The ferrule plug730 is disposed at the second end 703 of the adapter body 701. Theferrule plug 730 holds the optical ferrules 725 so that end faces of theferrules 725 are accessible within an interior 708 of the adapter body701. In certain implementations, the ferrule plug 730 includes keys 733that slide along keyways 709 defined along an interior surface of theadapter body 701. Interaction between the keys 733 and keyways 709ensures that the ferrules 725 correctly align with the ferrules 625 ofthe connector arrangement 600. When the twist-to-lock fastener 640 ofthe connector arrangement 600 is engaged with the fastening feature 706of the adapter 700, the optical ferrules 625, 725 optically coupletogether (e.g., see FIG. 48).

The adapter body 701 includes an internal wall 712 that retains theferrule plug 730 against forward axial movement within the adapter body701. The ferrule plug 730 includes a stepped section 734 that engageswith the internal wall 712 when the ferrule plug 730 is disposed withinthe adapter body 701. A lock arrangement retains the ferrule plug 730against rearward axial movement. For example, the ferrule plug 730 caninclude a flexible latch 732 that snaps into a groove 707 defined in theadapter body 701. In the example shown, the ferrule plug 730 includestwo flexible latches 732 at opposite sides of the ferrule plug 730. Eachlatch 732 snaps a respective groove 707 (see FIG. 47). In certainexamples, the inner surface of the adapter body 701 is ramped or taperedleading towards the grooves 707 to facilitate insertion of the ferruleplug 730.

The internal wall 712 is configured to abut the flanges 602 extendingforwardly of the connection end face 611 of the connector arrangement600 when the connector arrangement 600 is received at the adapter 700(see FIG. 49). In certain implementations, the ferrule plug 730 alsoincludes flanges 735 that extend towards the first end 702 of theadapter body 701. The flanges 735 are configured to abut the first end631 of the coupling housing 630 of the connector arrangement 600 whenthe connector arrangement 600 is received at the adapter 700 (see FIG.48).

The ferrule plug 730 is configured to hold a plurality of opticalferrules (e.g., multi-fiber ferrule) 725 terminating optical fibers. Theferrule plug 730 also can include one or more ferrule springs (e.g.,coil springs, leaf springs, etc.) 727. In an example, each adapterferrule 725 has a corresponding ferrule spring 727. In another example,one ferrule spring 728 can bias multiple of the adapter ferrules 725.

As shown in FIG. 45, the ferrule plug 730 can be formed from a firstplug housing 731 a and a second plug housing 732 b. The plug housings731 a, 732 b cooperate to hold the ferrules 725 therebetween. In certainexamples, a retainer 728 is disposed between a first row of the ferrules725 and a second row of the ferrules 725. In certain implementations,each plug housing 731 a, 731 b defines slots 736 in which the ferrules725 and ferrule springs 727 are disposed. Each plug housing 731 a, 731 balso includes a spring support 737 against which the spring 727 abuts.Each plug housing 731 a, 731 b also includes a retaining shoulder 738(FIG. 47) against which shoulders 726 f the ferrules 725 abut to inhibitthe ferrules 725 from passing axially through the ferrule plug 730.

FIGS. 50-53 illustrate another example connector housing arrangement 810suitable for use with the optical fiber connector arrangement 600. Forconvenience, the fiber optic connector arrangement having the connectorhousing arrangement 810 will be referred to with reference number 800.The multi-fiber cable 605 terminated by connector housing arrangement800 is anchored to the fiber take-up arrangement 660 (FIGS. 33-37) andexcess length of optical fibers 606 of the multi-fiber cable 605 isstored at a storage drum 662 therein. Distal ends of the optical fibers606 are routed through a furcation cable 695 (FIGS. 33-37) to theconnector housing arrangement 810. A first end of the furcation cable695 is anchored to the fiber take-up arrangement 660 (FIGS. 33-37). Asecond end of the furcation cable 695 is anchored to the connectorhousing arrangement 810 (see FIGS. 52 and 53). The distal ends of theoptical fibers 606 are connectorized at the ferrules 825 and disposed ata connection end 811 of the connector housing arrangement 810.

The example connector housing arrangement 810 holds the optical ferrules825 at the connection end 811. Furcation fibers, which are opticallycoupled to the optical fibers 606 of the multi-fiber cable 605, enterthe connector housing arrangement 810 at an anchor end 812, extendthrough a transition region 813, and terminate at the optical ferrules825.

In some implementations, the connector housing arrangement 810 includesa front housing 817 and a coupling sleeve 830. The front housing 817defines the connection end face 811, a ferrule mounting region 814, andthe anchor end 812. In certain implementations, the front housing 817includes one or more keying members 804 extending rearwardly from theend face 811. The keying members 804 are shaped and sized to mate withkeying passageways defined by a corresponding optical adapter and/or amating optical connector. In certain implementations, the keying members804 are offset from a centerline of the end face 811 to identify apreferred rotational orientation of the connector. In an example, thepreferred rotational orientation is based on which optical ferrules 825include pins and which optical ferrules 825 define pin holes. In anotherexample, the preferred rotational orientation is based on tuning of theoptical fibers within the ferrules 825.

In certain implementations, the anchor section 812 of the front housing817 defines a fiber passage 815 at which the optical fibers 606 extendthrough the anchor section 812. The fiber passage 815 provides access toa transition region 813 at which individual optical fibers 606 separateout to be terminated at the optical ferrules 825. In examples, theanchor section 812 defines two fiber passages 815. A first of the fiberpassages 815 leads to a first group of the optical ferrules 825 and asecond of the fiber passages 815 leads to a second group of the opticalferrules 825. In examples, each fiber passage 815 is sized to receivemultiple optical fibers 606. In examples, each fiber passage 815 isconfigured to receive one or more ribbons of optical fibers 606. Inanother example, each fiber passage 815 is configured to receive looseoptical fibers 606.

In certain implementations, the anchor end 812 also includes strengthmember cavities 816 a at which the strength members 697 of the furcationcable 695 are received. In examples, anchor boots 699 can be attached tothe strength members 697 of the furcation cable 695 and laterallyinserted into the cavities 816 a. Interaction between the anchor boots699 and retaining walls at the cavities 816 a axially retain thestrength members 697 against pulling out of the front housing 817. Incertain examples, epoxy can be applied to the strength members 697and/or anchor boots 699 at the strength member cavities 816 a. In otherexamples, the strength members 697 can be otherwise held at the cavities816 a. In examples, the strength member cavities 816 a do not connect tothe transition region 813.

In some implementations, the front housing 817 includes an integralhousing. In other implementations, however, the front housing 817includes at least a first housing section 819 a and a second housingsection 819 b. In certain implementations, the front housing 817includes a first housing section 819 a, a second housing section 819 b,and a third housing section 819 c (FIG. 52). In certain examples, theconnection end face 811 is defined fully by the first housing section819 a. In certain examples, the second and third housing sections 819 b,819 c are substantially identical.

In some implementations, the connection end face 811 of the firsthousing section 819 a defines one or more openings 814 a at which theoptical ferrules 825 are accessible. In certain examples, the firsthousing part 819 a defines all of the openings 814 a. In someimplementations, the first housing section 819 a is configured toreceive the optical ferrules 825 and/or the anchor boots 699 of thefurcation cable 695. In certain examples, the second and third housingsections 819 b, 819 c close cavities defined by the first housingsection 819 a to retain the optical ferrules 825 and/or the anchor boots699.

In certain implementations, the first housing section 819 a includes adivider 880 that separates the interior of the first housing section 819a into a first cavity 881 and a second cavity 882. Some of the opticalferrules 825 are disposed in the first cavity 881 and others of theoptical ferrules 825 are disposed in the second cavity 882. The secondhousing section 819 b closes the first cavity 881 and the third housingsection 819 c closes the second cavity 882. In certain examples, thesecond housing 819 b includes surfaces 616 b that closes the cavities816 a in which the anchor boots 699 are retained (see FIG. 52). In anexample, the third housing section 819 c also includes surfaces 616 bclosing the cavities 816 a in which the anchor boots 699 are retained.

In certain implementations, the first housing section 819 a defines aretention arrangement by which the optical ferrules 825 are at leasttemporarily retained prior to the second and third housing sections 819b, 819 c being coupled to the first housing section 819 a. For example,the optical ferrules 825 can be coupled to a retention mounts 885. Eachretention mount 885 can function as a spring support for the ferrulesprings (e.g., a coil spring, a leaf spring, etc.). Each retention mount885 includes one or more tabs 886 that fit into guides defined in thefirst housing section 819 a. For example, an entrance notch 883 can bedefined in sidewalls of the first housing section 819 a to receive thetabs 886. The entrance notches 883 can lead to channels 884 leadingtowards the divider 880. Interaction between the channels 884 and thetabs 886 maintains the optical ferrules 825 within the cavities 881, 882until the second and third housing sections 819 b, 819 c can close thecavities 881, 882.

The second and third housing sections 819 b, 819 c can include alignmentmembers to properly position the second and third housing sections 819b, 819 c relative to the first housing section 819 a. For example, thehousing sections 819 a, 819 b, 819 c can include mating tabs 820 a andslots 820 b. In the example shown, the second and third housing sections819 b, 819 c include tabs 820 a and the first housing section 819 adefines the corresponding slots 820 b. In certain examples, the housingsections 819 a, 819 b, 819 c latch together. In certain examples, thehousing sections 819 a, 819 b, 819 c are held together by the couplingsleeve 830.

The front housing 817 is elongated between the connection end 811 andthe anchor end 812. The coupling sleeve 830 is configured to extendaround the front housing 817 over a majority of the length of the fronthousing 817. The interior surface of the coupling sleeve 830 generallyfollows the exterior surface of the front housing 817. The couplingsleeve 830 is sized to retain the housing sections 819 a, 819 b of thefront housing 817 together when the coupling sleeve 830 is mounted aboutthe front housing 817.

In some implementations, a front portion of the front housing 817 stepsradially outwardly to define a rear-facing shoulder 821. An internalshoulder of the coupling sleeve 830 faces the rear-facing shoulder 821when the coupling sleeve 830 is mounted about the front housing 817. Theinteraction between the rear-facing shoulder 821 and the internalshoulder inhibits further forward movement of the coupling sleeve 830over the front housing 817. In certain implementations, a groove 823 isdefined at a rear of the front housing 817 (see FIG. 51). The couplingsleeve 830 includes a hook 839 configured to mate with the groove 823when the coupling sleeve 830 is mounted about the front housing 817. Inan example, the hook 839 is inwardly flexible relative to the fronthousing 817. The interaction between the hook 839 and the groove 823inhibits further rearward movement of the coupling sleeve 830 over thefront housing 817.

In certain implementations, one or more flanges 802 extend forwardly ofthe connection end face 811 (see FIG. 50) when the connector housingarrangement 810 is assembled. In certain examples, the flanges 802extend forwardly past the ferrules 825. In certain examples, the flanges802 form an interrupted wall extending forwardly of the connection endface 811. For example, interruptions in the wall may provide access tothe ferrules 825 for cleaning and/or polishing. In some implementations,the flanges 802 are integral with the front housing 817. In otherimplementations, the flanges 802 are integral with the coupling sleeve830 (see FIG. 51).

In some implementations, the coupling sleeve 830 carries a gasket (e.g.,an O-ring) 835 and includes an outwardly extending flange 834. In theexample shown, the gasket 835 is disposed between the flange 834 and theconnection end face 811. In other implementations, the gasket 835 can bemounted within the coupling sleeve 830 or over the front housing 817.

The connector housing arrangement 810 also is configured to seal to thefurcation cable 695. In certain examples, the coupling sleeve 830includes a reduced section 837 over which a portion of a strain-reliefboot extends. In some implementations, the strain-relief boot providesside load strain relief to the furcation cable 695. In certainimplementations, a heat recoverable sleeve 855 has a first portionextending over a jacket 698 of the furcation cable 695 and a secondportion extend over the reduced section 837 of the coupling sleeve 830.In certain examples, the reduced section 837 of the coupling sleeve 830can be textured (e.g., ribs, threads, bumps, etc.) to aid in axiallyretention of the heat recoverable sleeve 855.

The strain-relief boot is coupled to the coupling sleeve 830 (e.g., overthe heat recoverable sleeve 855) and extends over a portion of thefurcation cable 695. In certain examples, the reduced section 837defines a groove or slot 838 into which a ledge or teeth of thestrain-relief boot extend to hold the strain-relief boot to the couplingsleeve 830. In certain implementations, the coupling sleeve 830, theheat recoverable sleeve 855, and/or the strain-relief boot are shaped tomatch an outer periphery of the furcation cable 695. For example, insome implementations, the furcation cable 695 is a flat cable. In suchcases, the coupling sleeve 830, the heat recoverable sleeve 855, and/orthe strain-relief boot have a flattened profile corresponding to thefurcation cable 695. In other implementations, the furcation cable 695is a round cable.

A twist-to-lock fastener 840 is disposed over the coupling sleeve 830 toreleasably secure the optical fiber connector arrangement 800 to acomponent (e.g., an optical adapter). In examples, the gasket 835 can bedisposed on or in the twist-to-lock fastener 840 instead of or inaddition to connector housing arrangement 810. In examples, thetwist-to-lock fastener 840 included a threadable nut having an externalthreaded section 842 and a gripping section 845. When the connectorarrangement 800 is plugged into a port of a component, the threadedsection 842 of the twist-to-lock fastener 840 is engaged with aninternal thread of the component. In other examples, the twist-to-lockfastener 840 can include a bayonet connection. Rotating thetwist-to-lock fastener 840 relative to the component moves thetwist-to-lock fastener 840 axially against the outwardly extendingflange 834 of the coupling sleeve 830, thereby securing the connectorarrangement 800 to the component.

FIGS. 54-56 illustrate an example optical adapter 900 defining a port atwhich the optical connector arrangement 800 can be received. In someimplementations, the optical adapter 900 extends from a first end 902 toa second end 903. The first end 902 defines the port sized to receivethe optical connector arrangement 800. In some implementations, thesecond end 903 is configured to support optical ferrules 925 that matewith the optical ferrules 825 of the connector arrangement 800. In otherimplementations, the second end 903 defines a second port that canreceive an optical connector.

The adapter 900 includes a fastening feature 906 at the first end 902.The fastening feature 906 is configured to engage with the twist-to-lockfastener 840 of the connector arrangement 800 to hold the connectorarrangement 800 at the adapter 900. In some implementations, thefastening feature 906 includes internal threading (see FIG. 54). Inother implementations, the fastening features 906 include part of abayonet connection. When the twist-to-lock fastener 840 of the connectorarrangement 800 is engaged with the fastening feature 906 of the adapter900, the optical ferrules 825, 925 optically couple together.

The adapter 900 also includes a sealing surface 911 against which thegasket 835 of the connector arrangement 800 presses when the connectorarrangement 800 is disposed within the adapter 900. Accordingly, thefront housing 817 of the connector arrangement 800 can beenvironmentally sealed within the adapter 900.

The adapter 900 includes a flange 904 that extends radially outwardly.The adapter 900 defines external threads 905 adjacent the flange 904. Incertain implementations, the flange 904 is disposed between thefastening feature 906 and the external threads 905. A retaining ring 940is configured to move axially along the adapter 901. For example, in oneimplementation, the retaining ring 940 has an internal thread 941 thatengages the external threads 905 of the adapter 900. In certainexamples, the retaining ring 940 defines external notches 942 thatfacilitate rotating the retaining ring 940. The retaining ring 940cooperates with the flange 904 to secure a wall, panel, or other surfacetherebetween to mount the adapter 900 to the wall, panel, or othersurface. In some implementations, the flange 904 is disposed at thefirst end 902 of the adapter 900. In other implementations, flange 904is disposed closer to the second end 903 of the adapter 900. In stillother implementations, the flange 904 is disposed at any intermediateposition between the first and second ends 902, 903.

The adapter 900 is configured to retain a plurality of optical ferrules925 in a predetermined configuration to mate with the optical ferrules825 of the optical connector arrangement 800 when the optical connectorarrangement 800 is received at the adapter port. As shown in FIGS.55-56, the adapter 900 can include a first housing 910 and a secondhousing 930 that cooperate to retain the optical ferrules 925therebetween. In certain examples, the first housing 910 defines thefastening feature 906. In certain examples, the first housing 910defines the sealing surface 911. In certain examples, the first housing910 defines the flange 904. In certain examples, the first housing 910defines the fastening feature 906, the sealing surface 911, and theflange 904.

As shown in FIGS. 56-57, the adapter housings 910, 930 are configured toreceive a ferrule plug arrangement 920 that holds the optical ferrules925. In certain implementations, the ferrule plug arrangement 920includes a wall 922 that defines a plurality of openings or notches 923sized to receive portions of the optical ferrules 925. The ferrule plugarrangement 920 also includes flanges 926 that extend forwardly of theoptical ferrules 925. The flanges 926 define grooves 927 sized toreceive the keying members 804 of the optical connector arrangement 800to properly rotationally align the end face 811 of the optical connectorarrangement 800 with the optical ferrules 925.

In certain implementations, the plug arrangement 920 is configured to bereceived at the first adapter housing 910 in a predetermined rotationalposition. For example, in certain implementations, the plug arrangement920 includes rails 925 sized to fit in grooves 915 defined at a rear ofthe first adapter housing 910. The second adapter housing 930 couples tothe first adapter housing 910 to sandwich the plug arrangement 920therebetween. In certain examples, the second adapter housing 930threads to the first adapter housing 910. In other examples, the secondadapter housing 930 is latched, fastened by a bayonet, welded, orotherwise coupled to the first adapter housing 910.

In certain implementations, the ferrule plug arrangement 920 includes afirst piece 921 and a second piece 928. The first piece 921 includes thewall 922 that defines the ferrule openings 925. In certain examples, thefirst piece 921 includes the flanges 926. In certain examples, the firstpiece 921 also includes the rails 925. In certain implementations, thesecond piece 928 holds the optical ferrules 925 at the first piece 921.For example, ferrule springs (e.g., coil springs, leaf springs, etc.) ofthe optical ferrules 925 may seat on the second piece 928 to maintainthe optical ferrules 925 at the openings 923. In certain examples, thesecond piece 928 includes tabs 929 that align with the rails 925 of thefirst piece 921 when the first and second pieces 921, 928 are assembled.

The above specification, examples and data provide a completedescription of the manufacture and use of the composition of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended.

What is claimed is:
 1. A multi-fiber cable assembly comprising: amulti-fiber cable including a plurality of optical fibers, a strengthmember, and an outer jacket; a plurality of multi-fiber optical ferrulesthat each receive optical signals carried by some of the plurality ofoptical fibers; a fiber take-up arrangement at which excess length ofthe optical fibers is stored, the fiber take-up arrangement beingstructured to enable the optical fibers to be wrapped around the fibertake-up arrangement to manage the excess length; an anchor sectionconfigured to secure the strength member of the multi-fiber cable, theanchor section also defining a fiber passage through which the opticalfibers extends towards the optical ferrules; a connector housingarrangement including an outwardly extending flange; and a twist-to-lockfastener that mounts around the connector housing arrangement, thetwist-to-lock fastener having engagement structure that enables thetwist-to-lock fastener to couple to a component, the twist-to-lockfastener also having an interior abutment surface that aligns with theoutwardly extending flange of the connector housing arrangement tosecure the connector housing to the component.
 2. The multi-fiber cableassembly of claim 1, wherein the fiber take-up arrangement is disposedat the connector housing arrangement.
 3. The multi-fiber cable assemblyof claim 1, wherein the anchor section is disposed at the connectorhousing arrangement.
 4. The multi-fiber cable assembly of claim 1,further comprising a furcation cable extending between the fiber take-uparrangement and the connector housing arrangement, the furcation cablebeing more flexible than the multi-fiber cable.
 5. The multi-fiber cableassembly of claim 4, wherein the fiber take-up arrangement includes theanchor section.
 6. The multi-fiber cable assembly of claim 5, whereinthe anchor section includes a cavity at which an anchor boot attached tothe strength member of the multi-fiber cable is inserted.
 7. Themulti-fiber cable assembly of claim 5, wherein the anchor section is afirst anchor section, wherein the fiber take-up arrangement alsoincludes a second anchor section configured to receive a strength memberof the furcation cable.
 8. The multi-fiber cable assembly of claim 7,wherein the connector housing arrangement includes a third anchorsection configured to receive the strength member of the furcationcable.
 9. The multi-fiber cable assembly of claim 4, wherein the fibertake-up arrangement includes a mandrel arrangement configured to holdthe excess length of the optical fibers and a sealing arrangementproviding an environmental seal between the multi-fiber cable and thefurcation cable.
 10. The multi-fiber cable assembly of claim 9, whereinthe mandrel arrangement includes a first anchor body separated from asecond anchor body by a drum, the anchor bodies defining cavities toreceive strength members of the multi-fiber cable and the furcationcable.
 11. The multi-fiber cable assembly of claim 9, wherein thesealing arrangement includes a closure member configured to surround themandrel arrangement, first and second end members that attach toopposite ends of the closure member, and heat recoverable sleeves thatattach to the first and second end members.
 12. The multi-fiber cableassembly of claim 4, wherein connector housing arrangement holds themulti-fiber optical ferrules.
 13. The multi-fiber cable assembly ofclaim 12, wherein the connector housing arrangement includes a fronthousing and a coupling sleeve, the front housing defining a connectionend face at which the multi-fiber optical ferrules are accessible, thecoupling sleeve being configured to extend around the front housing overa majority of the length of the front housing.
 14. The multi-fiber cableassembly of claim 13, wherein the front housing defines an anchor end atwhich a strength member of the furcation cable can be retained.
 15. Themulti-fiber cable assembly of claim 14, wherein the front housingincludes a transition region disposed between the connection end faceand the anchor end.
 16. The multi-fiber cable assembly of claim 13,wherein the front housing includes a first housing section and a secondhousing section that cooperate to hold the multi-fiber optical ferrulestherebetween, wherein the coupling sleeve retains the first and secondhousing sections together.
 17. The multi-fiber cable assembly of claim13, wherein the coupling sleeve defines the outwardly extending flange.18. The multi-fiber cable assembly of claim 13, wherein the couplingsleeve carries an external gasket.
 19. The multi-fiber cable assembly ofclaim 13, wherein the front housing includes a first housing section, asecond housing section, and a third housing section, wherein theconnection end face is defined by the first housing section.
 20. Themulti-fiber cable assembly of claim 19, wherein the first housingsection defines a retention arrangement that temporarily holds theoptical ferrules at the first housing section until the second and thirdhousing sections are coupled to the first housing section.
 21. Themulti-fiber cable assembly of claim 1, wherein flanges extend forwardlyof the multi-fiber optical ferrules to form an interrupted wall.
 22. Themulti-fiber cable assembly of any of claim 1, further comprising anoptical adapter connected to the connector housing arrangement.
 23. Themulti-fiber cable assembly of claim 22, wherein the optical adaptercarries a plurality of second multi-fiber ferrules terminating secondoptical fibers, wherein the second multi-fiber ferrules carried by theoptical adapter align with the plurality of multi-fiber optical ferrulesso that the optical fibers of the multi-fiber cable are opticallycoupled to the second optical fibers.
 24. The multi-fiber cable assemblyof claim 23, wherein the optical adapter includes a first housing and asecond housing that sandwich a ferrule plug arrangement therebetween.